The following oops is seen during xfstest/565 when the 'test' (source of the copy) is NFS4.0 and 'scratch' (destination) is NFS4.2 [ 59.692458] run fstests generic/565 at 2020-08-01 05:50:35 [ 60.613588] BUG: kernel NULL pointer dereference, address: 0000000000000008 [ 60.624970] #PF: supervisor read access in kernel mode [ 60.627671] #PF: error_code(0x0000) - not-present page [ 60.630347] PGD 0 P4D 0 [ 60.631853] Oops: 0000 [#1] SMP PTI [ 60.634086] CPU: 6 PID: 2828 Comm: xfs_io Kdump: loaded Not tainted 5.8.0-rc3 #1 [ 60.637676] Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011 [ 60.639901] RIP: 0010:nfs4_check_serverowner_major_id+0x5/0x30 [nfsv4] [ 60.642719] Code: 89 ff e8 3e b3 b8 e1 e9 71 fe ff ff 41 bc da d8 ff ff e9 c3 fe ff ff e8 e9 9d 08 e2 66 0f 1f 84 00 00 00 00 00 66 66 66 66 90 <8b> 57 08 31 c0 3b 56 08 75 12 48 83 c6 0c 48 83 c7 0c e8 c4 97 bb [ 60.652629] RSP: 0018:ffffc265417f7e10 EFLAGS: 00010287 [ 60.655379] RAX: ffffa0664b066400 RBX: 0000000000000000 RCX: 0000000000000001 [ 60.658754] RDX: ffffa066725fb000 RSI: ffffa066725fd000 RDI: 0000000000000000 [ 60.662292] RBP: 0000000000020000 R08: 0000000000020000 R09: 0000000000000000 [ 60.666189] R10: 0000000000000003 R11: 0000000000000000 R12: ffffa06648258d00 [ 60.669914] R13: 0000000000000000 R14: 0000000000000000 R15: ffffa06648258100 [ 60.673645] FS: 00007faa9fb35800(0000) GS:ffffa06677d80000(0000) knlGS:0000000000000000 [ 60.677698] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 60.680773] CR2: 0000000000000008 CR3: 0000000203f14000 CR4: 00000000000406e0 [ 60.684476] Call Trace: [ 60.685809] nfs4_copy_file_range+0xfc/0x230 [nfsv4] [ 60.688704] vfs_copy_file_range+0x2ee/0x310 [ 60.691104] __x64_sys_copy_file_range+0xd6/0x210 [ 60.693527] do_syscall_64+0x4d/0x90 [ 60.695512] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 60.698006] RIP: 0033:0x7faa9febc1bd Signed-off-by: Dave Wysochanski <dwysocha@xxxxxxxxxx> --- fs/nfs/nfs4file.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/fs/nfs/nfs4file.c b/fs/nfs/nfs4file.c index 8e5d6223ddd3..24e4e6a4e94a 100644 --- a/fs/nfs/nfs4file.c +++ b/fs/nfs/nfs4file.c @@ -142,7 +142,8 @@ static ssize_t __nfs4_copy_file_range(struct file *file_in, loff_t pos_in, /* Only offload copy if superblock is the same */ if (file_in->f_op != &nfs4_file_operations) return -EXDEV; - if (!nfs_server_capable(file_inode(file_out), NFS_CAP_COPY)) + if (!nfs_server_capable(file_inode(file_out), NFS_CAP_COPY) || + !nfs_server_capable(file_inode(file_in), NFS_CAP_COPY)) return -EOPNOTSUPP; if (file_inode(file_in) == file_inode(file_out)) return -EOPNOTSUPP; -- 2.26.2